Tertiary alcohol derivative, polymer compound and photoresist composition

ABSTRACT

(1) A polymer compound for photoresist composition which is high in dissolution rate in a developing solution after exposure and small swelling at the development and (2) a compound which is a raw material for such a polymer compound are provided. Furthermore, (3) a photoresist composition containing the subject polymer compound is provided. In detail, a tertiary alcohol derivative represented by the following general formula (1) is provided. 
                         
(In the formula, R 1  and R 2  are taken together to form a ring together with a carbon atom to which R 1  and R 2  are bonded, and R 1  and R 2  as taken represent a linear, branched or cyclic alkylene group having from 2 to 9 carbon atoms, which may contain an oxygen atom at an arbitrary position; R 3  represents a hydrogen atom or a methyl group; W represents a linear, branched or cyclic alkylene group having from 1 to 10 carbon atoms; and n represents 0 or 1.)

TECHNICAL FIELD

The present invention relates to a novel tertiary alcohol derivative anda method for manufacturing the same. The tertiary alcohol derivativeobtained by the present invention is useful as a raw material compoundof a polymer compound obtained by polymerizing at least the subjecttertiary alcohol derivative as one of raw materials and of a photoresistcomposition containing the subject polymer compound as a component.

BACKGROUND ART

In recent years, in the electronic device manufacture field representedby the manufacture of integrated circuit devices, a demand for highintegration of devices is increasing, and therefore, a photolithographytechnology for forming a fine pattern is considered to be necessary. Forthat reason, the development of a photoresist composition adaptive withphotolithography using, as exposure light, radiations having awavelength of not more than 220 nm, for example, an ArF excimer laser(wavelength: 193 nm), an F₂ excimer laser (wavelength: 157 nm), etc. isdesired, and there have been proposed a number of photoresistcompositions of a chemical amplification type composed of an aciddissociable functional group-containing polymer compound and a compoundcapable of generating an acid upon irradiation with radiations(hereinafter referred to as “exposure”) (the latter compound will behereinafter referred to as “photo acid generator”). For example, thereare known photoresist compositions containing, as a component, a polymercompound having an adamantyl group-containing acrylic ester as aconstitutional unit as the acid dissociable functional group-containingpolymer compound (see Non-Patent Document 1 and Patent Document 1); andphotoresist compositions containing, as a component, a polymer compoundhaving a lactone ring-containing constitutional unit as the aciddissociable functional group-containing polymer compound (see PatentDocument 2).

-   Non-Patent Document 1: Journal of Photopolymer Science and    Technology, Vol. 9, No. 3, 475 to 487 (1996)-   Patent Document 1: JP-A-9-73173-   Patent Document 2: JP-A-2004-46206

DISCLOSURE OF THE INVENTION Problems that the Invention is to Solve

In recent years, under the circumstances that much more fine fabricationof a pattern rule in electronic devices is demanded, photoresistcompositions containing, as a component, a polymer compound having alactone based protective group-containing constitutional unit, which areimproved in sensitivity, resolution, dry etching resistance, etc. wereproposed (see Patent Documents 3 and 4). However, it is the presentsituation that it is hard to say that these photoresist compositionshave sufficient performance. The most serious problem is line widthfluctuation of a pattern to be formed, which is called “line widthroughness” (LWR), and it is required that its tolerable value is lessthan 8% of the line width (see Non-Patent Document 2). In order toimprove LWR, it is necessary that pattern deformation to be caused dueto swelling is suppressed. In order to suppress the pattern deformationto be caused due to swelling, it is necessary that the polymer compoundwhich is the photoresist composition component is hardly swollen.However, in polymer compounds prepared through a combination ofpolymerizable compounds which have hitherto been known, those having aperformance on a satisfactory level are not always obtained. For thatreason, the development of a polymer compound for photoresistcomposition which is more hardly swollen is still desired earnestly.

-   Patent Document 3; JP-A-11-223950-   Patent Document 4: JP-A-2000-267287-   Non-Patent Document 2: International Technology Roadmap for    Semiconductors (ITRS) 2006, “Lithography”, page 7

As a result of extensive and intensive investigations regarding alactone based protective group-containing polymer compound to be usedfor a photoresist composition of a chemical amplification type for thepurpose of solving the foregoing problems of the background art, thepresent invention has been made. Its object is to provide (1) a polymercompound for photoresist composition which is small swelling at thedevelopment and (2) a polymerizable compound which is a raw material forsuch a polymer compound; and further to provide (3) a photoresistcomposition with improved LWR comprising the subject polymer compound.

The present inventors made extensive and intensive investigationsregarding a relationship between properties of a polymer compound forphotoresist composition and swelling properties of a photoresistcomposition using it as a component at the development. As a result, thepresent inventors have found out that when a polymer compound forphotoresist composition having a high dissolution rate to a developingsolution after exposure is used, swelling can be suppressed.Furthermore, the present inventors have found a polymer compound havinga specified structure as the polymer compound for photoresist componentshaving a high dissolution rate to a developing solution after exposureand a polymerizable compound which is a raw material for such a polymercompound, leading to accomplishment of the invention.

Means for Solving the Problems

According to the present invention, the foregoing problems have beenachieved by providing:

1. A tertiary alcohol derivative represented by the following generalformula (1) (hereinafter referred to as “tertiary alcohol derivative(1)”):

(in the formula, R¹ and R² are taken together to form a ring togetherwith a carbon atom to which R¹ and R² are bonded, and R¹ and R² as takenrepresent a linear, branched or cyclic alkylene group having from 2 to 9carbon atoms, which may contain an oxygen atom at an arbitrary position;R³ represents a hydrogen atom or a methyl group; W represents a linear,branched or cyclic alkylene group having from 1 to 10 carbon atoms; andn represents 0 or 1);2. The tertiary alcohol derivative (1), wherein W is a methylene groupor an ethane-1,1-diyl group;3. The tertiary alcohol derivative (1), wherein n is 0;4. A method for manufacturing the tertiary alcohol derivative (1)comprising, as a first step, oxidizing a carboxylic acid derivativerepresented by the following general formula (2) (hereinafter referredto as “carboxylic acid derivative (2)”):

(in the formula, R¹ and R² are the same as defined above; and R⁴represents an alkyl group having from 1 to 10 carbon atoms, an arylgroup having from 6 to 12 carbon atoms or an aralkyl group having from 7to 13 carbon atoms)in the presence of a water, or oxidizing a carboxylic acid derivativerepresented by the following general formula (2′) (hereinafter referredto as “carboxylic acid derivative (2′)):

(in the formula, R¹ and R² are the same as defined above), therebyobtaining a tertiary alcohol represented by the following generalformula (3) (hereinafter referred to as “tertiary alcohol (3)”):

(in the formula, R¹ and R² are the same as defined above); and, as asecond step, subsequently allowing the tertiary alcohol (3) to reactwith a polymerizable group introducing agent, or allowing the tertiaryalcohol (3) to react with a connecting group introducing agent and thento react with a polymerizable group introducing group;5. A method for manufacturing the tertiary alcohol (3) comprisingoxidizing the carboxylic acid derivative (2) in the presence of water oroxidizing the carboxylic acid derivative (2′);6. The tertiary alcohol (3);7. A polymer compound obtained by polymerizing at least the tertiaryalcohol derivative (1) as one of raw materials (this polymer compoundwill be hereinafter referred to as “polymer compound (4)”); and8. A photoresist composition comprising the polymer compound (4) and aphoto acid generator.

Advantages of the Invention

According to the present invention, it is possible to provide (1) apolymer compound for photoresist composition which has a highdissolution rate to a developing solution after exposure and which issmall swelling at the development and (2) a polymerizable compound whichis a raw material of the subject polymer compound; and it is alsopossible to provide (3) a photoresist composition containing the subjectpolymer compound, which is improved in LWR.

BEST MODES FOR CARRYING OUT THE INVENTION

In the foregoing formulae, examples of the linear, branched or cyclicalkylene group having from 2 to 9 carbon atoms, which is represented byR¹ and R² as taken and which may contain an oxygen atom at an arbitraryposition, include a 1,2-ethanediyl group, a 1,3-propanediyl group, a1,4-butanediyl group, a 1,5-pentanediyl group, a 1,6-hexanediyl group, a(cyclopentane-1′,3′-diyl)methyl group, a(2′,2′,3′-trimethylcyclopentane-1′,3′-diyl)methyl group, abicyclo[3,3,1]nonane-3,7-diyl group, a 2-oxabutane-1,4-diyl group, a2-oxapentane-1,5-diyl group and a 3-oxopentane-1,5-diyl group. Examplesof the ring structure having from 3 to 10 carbon atoms, which is formedby R¹ and R² together with a carbon atom to which R¹ and R² are bondedand which may contain an oxygen atom at an arbitrary position, include acyclopropane ring, a cyclobutane ring, a cyclopentane ring, acyclohexane ring, a cycloheptane ring, a camphor ring, a norbornanering, an adamantane ring, a tetrahydrofuran ring and a tetrahydropyranring.

Examples of the linear, branched or cyclic alkylene group having from 1to 10 carbon atoms represented by W of the tertiary alcohol derivative(1) include a methylene group, an ethane-1,1-diyl group, anethane-1,2-diyl group, a propane-1,1-diyl group, a propane-1,2-diylgroup, a propane-1,3-diyl group, a pentane-1,5-diyl group, ahexane-1,1-diyl group and a cyclohexane-1,4-diyl group. Of these, amethylene group and an ethane-1,1-diyl group are preferable.

Examples of the alkyl group represented by R⁴ of the ester compound (2)include an ethyl group and a methyl group; examples of the aryl groupinclude a phenyl group; and examples of the aralkyl group include abenzyl group.

n of the tertiary alcohol derivative (1) is 0 or 1, with 0 beingpreferable.

Specific examples of the tertiary alcohol derivative (1) include thefollowing formulae (1-a) to (1-l), but it should not be construed thatthe present invention is limited thereto:

The tertiary alcohol derivative (1) can be, for example, manufactured bythe following process, but it should not be construed that the presentinvention is limited thereto.

(In the formulae, R¹, R², R³ and R⁴ are the same as defined.)

The respective steps axe hereunder described.

A method for manufacturing the carboxylic acid derivative (2) orcarboxylic acid derivative (2′) to be used in the first step is notparticularly limited. The carboxylic acid derivative (2) can be, forexample, manufactured by the Johnson-Claisen rearrangement reactionbetween a corresponding allyl alcohol and a corresponding trialkylorthoacetate, triaryl orthoacetate or triaralkyl orthoacetate in thepresence of an acid catalyst. The carboxylic acid derivative (2′) canbe, for example, manufactured by oxidation of a corresponding alcohol orhydrolysis of the carboxylic acid derivative (2) which can bemanufactured by the foregoing method.

Examples of the oxidizing agent to be used in the first step includepercarboxylic acids, for example, performic acid, peracetic acid,m-chloroperbenzoic acid, etc.; metal peroxides obtained by allowingsodium tungstenate, vanadium oxide, etc. to react with hydrogenperoxide, t-butylhydroperoxide, etc.; and osmium tetroxide. Above all,it is the most preferable that performic acid is formed in a system fromformic acid and hydrogen peroxide and used. From the viewpoints ofeconomy and easiness of post-treatment, the use amount of the oxidizingagent is preferably in the range of from 0.8 times by mole to 10 timesby mole, and more preferably in the range of from 1 time by mole to 2times by mole relative to the carboxylic acid derivative (2) orcarboxylic acid derivative (2′).

In case of using the carboxylic acid derivative (2), the first step iscarried out in the presence of water. The use amount of water issufficient to be 1 time by mole or more relative to the carboxylic acidderivative (2). In case of using the carboxylic acid derivative (2′),the first step can be carried out in the presence or absence of water.

The first step can be carried out in the presence or absence of asolvent. The solvent is not particularly limited so far as it does nothinder the reaction, and examples thereof include water; aliphatichydrocarbons, for example, hexane, heptane, octane, etc.; aromatichydrocarbons, for example, toluene, xylene, cymene, etc.; halogenatedhydrocarbons, for example, methylene chloride, dichloroethane, etc.;ethers, for example, tetrahydrofuran, diisopropyl ether, etc.; andcarboxylic acids, for example, formic acid, acetic acid, etc. Thesesolvents may be used singly or may be used in admixture of two or morekinds thereof. In case of using a solvent, from the viewpoints ofeconomy and easiness of post-treatment, the use amount thereof ispreferably in the range of from 0.1 times by mass to 10 times by mass,and more preferably in the range of from 0.1 times by mass to 5 times bymass relative to the carboxylic acid derivative (2) or carboxylic acidderivative (2′).

A reaction temperature of the first step varies depending upon the kindof each of the carboxylic acid derivative (2) or carboxylic acidderivative (2′) and the oxidizing agent to be used, and in general, itis preferably in the range of from −40° C. to 100° C.

The reaction time of the first step varies depending upon the carboxylicacid derivative (2) or carboxylic acid derivative (2′) and the oxidizingagent to be used and the reaction temperature, and in general, it ispreferably in the range of from 0.5 hours to 48 hours, and morepreferably in the range of from 1 hour to 24 hours.

The reaction of the first step can be terminated by adding a reducingagent. Examples of the reducing agent include sulfites, for example,sodium sulfite, sodium hydrogensulfite, etc.; and sulfides, for example,dimethyl sulfide, diphenyl sulfide, etc. The use amount of the reducingagent is preferably in the range of from 1 equivalent to 5 equivalentsto the excess of the oxidizing agent.

The thus obtained tertiary alcohol (3) can be isolated by an operationwhich is usually employed in isolating an organic compound, for example,solvent extraction, distillation, column chromatography,recrystallization, etc.

The thus obtained tertiary alcohol (3) is a novel compound.

Next, the second step is described.

In the case where n of the tertiary alcohol derivative (1) is 0, thesecond step is carried out by allowing the tertiary alcohol (3) asobtained in the first step to react with a compound represented by aformula: CH₂═CR³COX (in the formula, R³ is the same as defined above); aformula: (CH₂═CR³CO)₂O (in the formula, R³ is the same as definedabove); a formula: CH₂═CR³COOC(═O)R⁵ (in the formula, R³ is the same asdefined above; and R⁵ represents a t-butyl group or a2,4,6-trichlorophenyl group); or a formula: CH₂═CR³COOSO₂R⁶ (in theformula, R³ is the same as defined above; and R⁶ represents a methylgroup or a p-tolyl group) (such a compound will be hereinafter referredto “polymerizable group introducing agent A”) in the presence of a basicsubstance (this reaction step will be hereinafter referred to as “secondstep A”). In the case where n of the tertiary alcohol derivative (1) is1, the second step is carried out by allowing the tertiary alcohol (3)obtained in the first step to react with a compound represented by aformula; X—W—COX (in the formula, W is the same as defined above; and Xrepresents a chlorine atom, a bromine atom or an iodine atom); aformula: (X—W—C(═O))₂O (in the formula, W and X are the same as definedabove); a formula: X—W—COOC(═O)R⁷ (in the formula, X and W are the sameas defined above; and R⁷ represents a t-butyl group or a2,4,6-trichlorophenyl group); or a formula: X—W—COOSO₂R⁸ (in theformula, X and W are the same as defined above; and R⁸ represents amethyl group or a p-tolyl group) (such a compound will be hereinafterreferred to “connecting group introducing agent B1”) in the presence ofa basic substance (this reaction step will be hereinafter referred to as“second step B-1”); and subsequently allowing a reaction product toreact with a compound represented by a formula: CH₂═CR³COOM (in theformula, R³ is the same as defined above; and M represents a sodium atomor a potassium atom) (such a compound will be hereinafter referred to“polymerizable group introducing agent B2”) (this reaction step will behereinafter referred to as “second step B-2”). The second step A tosecond step B are hereunder successively described.

Specific examples of the tertiary alcohol derivative (1) wherein n is 0,which is manufactured by the second step A, include (1-a) to (1-j).

As to the polymerizable group introducing agent A to be used in thesecond step A, specific examples of the compound represented by theformula: CH₂═CR³COX include acryloyl chloride and methacryloyl chloride;specific examples of the compound represented by the formula:(CH₂═CR³CO)₂O include acrylic anhydride and methacrylic anhydride;specific examples of the compound represented by the formula:CH₂═CR³COOC(═O)R⁵ include acrylic pivalic anhydride, acrylic2,4,6-trichlorobenzoic anhydride, methacrylic pivalic anhydride andmethacrylic 2,4,6-trichlorobenzoic anhydride; and specific examples ofthe compound represented by the formula; CH₂═CR³COOSO₂R⁶ include acrylicmethanesulfonic anhydride, acrylic p-toluenesulfonic anhydride,methacrylic methanesulfonic anhydride and methacrylic p-toluenesulfonicanhydride. From the viewpoints of economy and easiness ofpost-treatment, the use amount of the polymerizable group introducingagent A is preferably in the range of from 0.8 times by mole to 5 timesby mole, and more preferably in the range of from 0.8 times by mole to 3times by mole relative to the tertiary alcohol (3).

Examples of the basic substance to be used in the second step A includesodium hydride, potassium hydride, sodium hydroxide, potassiumhydroxide, sodium carbonate, potassium carbonate, triethylamine,pyridine, tributylamine and diazabicyclo[2,2,2]octane. From theviewpoints of economy and easiness of post-treatment, the use amount ofthe basic substance is preferably in the range of from 0.8 times by moleto 5 times by mole, and more preferably in the range of from 0.8 timesby mole to 3 times by mole relative to the tertiary alcohol (3).

The second step A can be carried out in the presence or absence of asolvent. Though the solvent is not particularly limited so far as itdoes not hinder the reaction, aliphatic hydrocarbons, for example,hexane, heptane, octane, etc.; aromatic hydrocarbons, for example,toluene, xylene, cymene, etc.; halogenated hydrocarbons, for example,methylene chloride, dichloroethane, etc.; ethers, for example,tetrahydrofuran, diisopropyl ether, etc.; and nitrites, for example,acetonitrile, benzonitrile, etc. are favorable. These solvents may beused singly or may be used in admixture of two or more kinds thereof. Incase of using a solvent, from the viewpoints of economy and easiness ofpost-treatment, the use amount thereof is preferably in the range offrom 0.1 times by mass to 10 times by mass, and more preferably in therange of from 0.1 times by mass to 5 times by mass relative to thetertiary alcohol (3).

A reaction temperature of the second step A varies depending upon thekind of each of the polymerizable group introducing agent A, thetertiary alcohol (3) and the basic substance to be used, and in general,it is preferably in the range of from −50° C. to 80° C.

The reaction time of the second step A varies depending upon each of thepolymerizable group introducing agent A, the tertiary alcohol (3) andthe basic substance to be used and the reaction temperature, and ingeneral, it is preferably in the range of from 0.5 hours to 48 hours,and more preferably in the range of from 1 hour to 24 hours.

The reaction of the second step A can be terminated by adding water oran alcohol. Examples of the alcohol include methanol, ethanol,n-propanol and i-propanol. A mixture of water and an alcohol can also beused. The use amount of water or the alcohol may be one time by mole ormore relative to the excess of the polymerizable group introducing agentA. When the use amount is small, there may be the case where the excessof the polymerizable group introducing agent A cannot be completelydecomposed, thereby forming a by-product.

Next, the second step B is described. Specific examples of the tertiaryalcohol derivative (1) wherein n is 1, which is manufactured by thesecond step B, include (1-k) to (1-l).

As to the connecting group introducing agent B1 to be used in the secondstep B-1, specific examples of the compound represented by the generalformula: X—W—COX include chloroacetyl chloride, 2-chloropropionylchloride and 2-bromo-2-methylpropionic acid bromide; specific examplesof the compound represented by the formula: X—W—COOC(═O)R⁷ includechloroacetic acid pivalic anhydride, chloroacetic acid2,4,6-trichlorobenzoic anhydride, 2-chloropropionic acid pivalicanhydride and 2-chloropropionic acid 2,4,6-trichlorobenzoic anhydride;specific examples of the compound represented by the formula:X—W—COOSO₂R⁸ include chloroacetic acid methanesulfonic anhydride,chloroacetic acid p-toluenesulfonic anhydride, 2-chloropropionic acidmethanesulfonic anhydride and 2-chloropropionic acid p-toluenesulfonicanhydride; and specific examples of the compound represented by theformula: (X—W—C(═O))₂O include chloroacetic anhydride and2-chloropropinic anhydride. From the viewpoints of economy and easinessof post-treatment, the use amount of the connecting group introducingagent B1 is preferably in the range of from 0.8 times by mole to 5 timesby mole, and more preferably in the range of from 0.8 times by mole to 3times by mole relative to the tertiary alcohol (3).

Examples of the basic substance to be used in the second step B-1include sodium hydride, potassium hydride, sodium hydroxide, potassiumhydroxide, sodium carbonate, potassium carbonate, triethylamine,pyridine, tributylamine and diazabicyclo[2,2,2]octane. From theviewpoints of economy and easiness of post-treatment, the use amount ofthe basic substance is preferably in the range of from 0.8 times by moleto 5 times by mole, and more preferably in the range of from 0.8 timesby mole to 3 times by mole relative to the tertiary alcohol (3).

The second step B-1 can be carried out in the presence or absence of asolvent. Though the solvent is not particularly limited so far as itdoes not hinder the reaction, aliphatic hydrocarbons, for example,hexane, heptane, octane, etc.; aromatic hydrocarbons, for example,toluene, xylene, cymene, etc.; halogenated hydrocarbons, for example,methylene chloride, dichloroethane, etc.; ethers, for example,tetrahydrofuran, diisopropyl ether, etc.; and nitrites, for example,acetonitrile, benzonitrile, etc. are favorable. These solvents may beused singly or may be used in admixture of two or more kinds thereof. Incase of using a solvent, from the viewpoints of economy and easiness ofpost-treatment, the use amount thereof is preferably in the range offrom 0.1 times by mass to 10 times by mass, and more preferably in therange of from 0.1 times by mass to 5 times by mass relative to thetertiary alcohol (3).

A reaction temperature of the second step B-1 varies depending upon thekind of each of the connecting group introducing agent B1, the tertiaryalcohol (3) and the basic substance to be used, and in general, it ispreferably in the range of from −50° C. to 80° C.

The reaction time of the second step B-1 varies depending upon the kindof each of the connecting group introducing agent B1, the tertiaryalcohol (3) and the basic substance to be used and the reactiontemperature, and in general, it is preferably in the range of from 0.5hours to 48 hours, and more preferably in the range of from 1 hour to 24hours.

The reaction of the second step B-1 can be terminated by adding water oran alcohol. Examples of the alcohol include methanol, ethanol,n-propanol and i-propanol. A mixture of water and an alcohol can also beused. The use amount of water or the alcohol may be one time by mole ormore relative to the excess of the connecting group introducing agentB1. When the use amount is small, there may be the case where the excessof the connecting group introducing agent B1 cannot be completelydecomposed, thereby forming a by-product.

An intermediate obtained in the second step B-1 can be used in thesecond step B-2 upon being isolated from the reaction mixed solution oras the reaction mixed solution stands. In case of isolation from thereaction mixed solution, a method which is usually employed as anisolation method of an organic compound can be employed.

Specific examples of the polymerizable group introducing agent B2 to beused in the second step B-2 include sodium acrylate, potassium acrylate,sodium methacrylate and potassium methacrylate. As the polymerizablegroup introducing agent B2, a commercially available material can alsobe used; and a mixture prepared by mixing acrylic acid or methacrylicacid and potassium carbonate, sodium carbonate, potassium hydroxide orsodium hydroxide in the reaction solution can be used, too. Of these, itis preferable to use a mixture prepared in the reaction mixture. Fromthe viewpoints of economy and easiness of post-treatment, the use amountof the polymerizable group introducing agent B2 is preferably in therange of from 0.8 times by mole to 5 times by mole, and more preferablyin the range of from 0.8 times by mole to 3 times by mole relative tothe intermediate obtained in the second step B-1.

In the second step B-2, it is preferable that, for example, potassiumiodide, sodium iodide, tetrabutylammonium iodide, tetrabutylammoniumbromide or the like is used as an activating agent as the need arises.In case of using an activating agent, the use amount thereof ispreferably in the range of from 0.001 times by mole to 0.5 times by molerelative to the intermediate obtained in the second step B-1, and fromthe viewpoints of economy and easiness of post-treatment, it is morepreferably in the range of from 0.005 times by mole to 0.3 times bymole.

The second step B-2 can be carried out in the presence or absence of asolvent. The solvent is not particularly limited so far as it does nothinder the reaction, and examples thereof include aliphatichydrocarbons, for example, hexane, heptane, octane, etc.; aromatichydrocarbons, for example, toluene, xylene, cymene, etc.; halogenatedhydrocarbons, for example, methylene chloride, dichloroethane, etc.;ethers, for example, tetrahydrofuran, diisopropyl ether, etc.; andamides, for example, N,N-dimethylformamide, N,N-dimethylacetamide,N-methylpyrrolidone, etc. These solvents may be used singly or may beused in admixture of two or more kinds thereof. In case of using asolvent, from the viewpoints of economy and easiness of post-treatment,the use amount thereof is preferably in the range of from 0.1 times bymass to 10 times by mass, and more preferably in the range of from 0.1times by mass to 5 times by mass relative to the intermediate obtainedin the second step B-1.

A reaction temperature of the second step B-2 varies depending upon thekind of each of the polymerizable group introducing agent B2 to be usedand the intermediate obtained in the second step B-1, and in general, itis preferably in the range of from −50° C. to 80° C.

The reaction time of the second step B-2 varies depending upon the kindof each of the polymerizable group introducing agent B2 to be used andthe intermediate obtained in the second step B-1 and the reactiontemperature, and in general, it is preferably in the range of from 0.5hours to 48 hours, and more preferably in the range of from 1 hour to 24hours.

It is preferable that the tertiary alcohol derivative (1) obtainedthrough the second step A or the second step B-1 and second step B-2 isseparated and purified in the usual way as the need arises. For example,after washing with water, the reaction mixture can be purified by amethod which is employed for usual separation and purification of anorganic compound, for example, concentration, distillation, columnchromatography, recrystallization, etc. Also, it is possible to reducethe content of a metal in the obtained tertiary alcohol derivative (1)by filtration after addition of a chelating agent, for example,nitrilotriacetic acid, ethylenediaminetetraacetic acid, etc.; or atreatment by a metal removal filter, for example, ZETA PLUS (a tradename, manufactured by CUNO Incorporated), PROTEGO (a trade name,manufactured by Nippon Mykrolis K. K.), etc. as the need arises.

The polymer compound (4) of the present invention is a polymer compoundobtained by homopolymerizing the tertiary alcohol derivative (1) or apolymer compound obtained by copolymerizing the tertiary alcoholderivative (1) and other polymerizable compound. In case of a copolymer,it contains a constitutional unit on the basis of the tertiary alcoholderivative (1) in an amount preferably in the range of from 10 to 80% bymole, and more preferably in the range of from 20 to 70% by mole.Specific examples of the constitutional unit on the basis of thetertiary alcohol derivative (1) include those represented by thefollowing formulae (1′-a) to (1′-l), but it should not be construed thatthe present invention is limited thereto.

Examples of other copolymerizable compound to be copolymerized(hereinafter referred to as “copolymerizable monomer”) include compoundsrepresented by the following formulae (I) to (X) (in the formulae, R⁹,R¹⁰, R¹¹, R¹², R¹⁴, R¹⁵, R¹⁶, R¹⁷ and R¹⁸ each independently representsa hydrogen atom or a methyl group; and R¹³ represents a hydrogen atom orCOOR¹⁹ (R¹⁹ represents an alkyl group, for example, a methyl group, anethyl group, an n-propyl group, etc.; or a cycloalkyl group, forexample, a cyclohexyl group, a cyclopentyl group, a 2-adamantyl group,etc.)). But, it should not be construed that the present invention islimited thereto. The copolymerizable monomer can be used singly or canbe used in admixture of two or more kinds thereof as the need arises.

Specific examples of the polymer compound (4) of the present inventioninclude the following polymer compounds, but it should not be construedthat the present invention is limited thereto. (R⁹, R¹⁰, R¹¹, R¹², R¹⁴,R¹⁵, R¹⁶, R¹⁷ and R¹⁸ are the same as defined above; and l, m and n eachrepresents a molar ratio of the constitutional unit.)

Though the polymer compound (4) of the present invention is notparticularly limited with respect to its weight average molecular weight(Mw), a polymer having an Mw according to the following measurementmethod in the range of from 500 to 50,000, and preferably in the rangeof from 1,000 to 30,000 is useful as a raw material of a polymercomposition for photoresist. In the measurement, such Mw can bedetermined by a gel permeation chromatography method (GPC method) usinga column prepared by connecting two columns of TSK-gel SUPER HZM-H (atrade name, manufactured by Tosoh Corporation; diameter: 4.6 mm, length:150 mm) and one column of TSK-gel SUPER HZ2000 (a trade name,manufactured by Tosoh Corporation; diameter: 4.6 mm, length: 150 mm) inseries; using a differential refractometer (RI) as a detector andtetrahydrofuran as an eluting solution; measuring under a condition at acolumn temperature of 40° C., a temperature of RI of 40° C. and a flowrate of the eluting solution of 0.35 mL/min; and calculating accordingto a calibration curve prepared using standard polystyrene. Also, bydividing a weight average molecular weight (Mw) by a number averagemolecular weight (Mn), dispersity (Mw/Mn) is determined.

The dispersity of the polymer compound (4) of the present invention ispreferably in the range of from 1.0 to 2.5, and more preferably in therange of from 1.0 to 2.0.

The polymer compound (4) of the present invention is obtained by feedingthe tertiary alcohol derivative (1) and a radical polymerizationinitiator and optionally, one or more kinds of copolymerizable monomers,a solvent and a chain transfer agent into a reactor and subjecting themixture to a radical polymerization reaction. Such a polymerizationreaction is hereunder described.

In the manufacture of the polymer compound (4) of the present invention,the tertiary alcohol derivative (1) as a monomer and the copolymerizablemonomer are polymerized in a corresponding molar ratio of theconstitutional units in the desired polymer compound (4). That is,similar to a manner which is carried out in a general radicalpolymerization reaction, taking into consideration a polymerization rateratio of each monomer and a corresponding molar ratio of theconstitutional units in the desired polymer compound (4), by properlyregulating a molar ratio of the tertiary alcohol derivative (1) and thecopolymerizable monomer to be provided for the radical polymerizationreaction, the polymer compound (4) having a desired molar ratio of theconstitutional units can be obtained.

Examples of the radical polymerization initiator to be used for themanufacture of the polymer compound (4) of the present invention includehydroperoxide compounds, for example, t-butylhydroperoxide, etc.;dialkylperoxide compounds, for example, di-t-butylperoxide, etc.; diacylperoxide compounds, for example, benzoyl peroxide, etc.; and azocompounds, for example, 2,2′-azobisisobutyronitrile, dimethyl2,2′-azobisisobutyrate, etc. Above all, it is preferable to use an azocompound, for example, 2,2′-azobisisobutyronitrile, dimethyl2,2′-azobisisobutyrate, etc. The use amount of the radicalpolymerization initiator is preferably in the range of from 0.5% by moleto 20% by mole, and more preferably in the range of from 1 to 15% bymole relative to the total molar number of the polymerizable compounds,namely the total molar number of the tertiary alcohol derivative (1) andother copolymerizable monomer. Similar to a general radicalpolymerization reaction, the molecular weight of the polymer compound(4) can be regulated by the use amount of the radical polymerizationinitiator.

In the manufacture of the polymer compound (4) of the present invention,a chain transfer agent may be used as the need arises. Examples of thechain transfer agent include thiol compounds, for example,dodecanethiol, mercaptoethanol, mercaptopropanol, mercaptoacetic acid,mercaptopropionic acid, etc. These may be used singly or may be used inadmixture of two or more kinds thereof. In case of using a chaintransfer agent, the use amount thereof is preferably in the range offrom 0.5% by mole to 20% by mole, and more preferably in the range offrom 1 to 15% by mole relative to the total molar number of thepolymerizable compounds, namely the total molar number of the tertiaryalcohol derivative (1) and other copolymerizable monomer.

It is preferable that the manufacture of the polymer compound (4) of thepresent invention is carried out in a solvent. The solvent is notparticularly limited so far as it does not hinder the polymerizationreaction, and examples thereof include glycol ethers, for example,propylene glycol monoethyl ether, propylene glycol monomethyl etheracetate, ethylene glycol monomethyl ether, ethylene glycol monomethylether acetate, ethylene glycol monobutyl ether, ethylene glycolmonobutyl ether acetate, etc.; esters, for example, ethyl lactate,methyl 3-methoxypropionate, methyl acetate, ethyl acetate, propylacetate, etc.; ketones, for example, acetone, methyl ethyl ketone,methyl isopropyl ketone, methyl isobutyl ketone, methyl amyl ketone,cyclohexanone, etc.; and ethers, for example, diethylether,diisopropylether, dibutyl ether, tetrahydrofuran, dioxane, etc. Thesemay be used singly or may be used in admixture of two or more kindsthereof. From the viewpoints of economy and easiness of post-treatment,in general, the use amount of the solvent is preferably in the range offrom 0.5 times by mass to 20 times by mass, and preferably in the rangeof from 1 time by mass to 10 times by mass relative to the total mass ofthe polymerizable compounds, namely the total molar number of thetertiary alcohol derivative (1) and other copolymerizable monomer.

In the manufacture of the polymer compound (4) of the present invention,the polymerization method is not particularly limited, and a knownmethod which is employed in manufacturing an acrylic polymer, includinga solution polymerization method, an emulsion polymerization method, asuspension polymerization method and a bulk polymerization method, canbe employed. Above all, it is preferable to employ a solutionpolymerization method.

From the viewpoint of stability of the tertiary alcohol derivative (1)and the polymer compound (4), the polymerization temperature in themanufacture of the polymer compound (4) of the present invention is inthe range of from 40° C. to 150° C., and preferably in the range of from60° C. to 120° C.

The manufacturing time of the polymer compound (4) of the presentinvention varies depending upon the kind and amount of the tertiaryalcohol derivative (1); the kind and amount of the copolymerizablemonomer; the kind and amount of the radical polymerization initiator;the kind and amount of the solvent; the temperature of thepolymerization reaction; and the like, and it is generally in the rangeof from 30 minutes to 48 hours, and preferably in the range of from 1hour to 24 hours.

It is possible to isolate the polymer compound (4) to be contained inthe thus obtained reaction mixed solution by a usual operation, forexample, gel permeation chromatography, reprecipitation, etc. Also, itis possible to regulate the molecular weight and dispersity by a usualoperation, for example, gel permeation chromatography, reprecipitation,etc. Furthermore, if desired, it is possible to reduce the content of ametal in the polymer compound (4) by dissolving the isolated polymercompound (4) in an appropriate solvent and subjecting the solution to anoperation, for example, a treatment with a chelating agent, a treatmentby a metal removal filter, etc.

Examples of the solvent to be used for the foregoing reprecipitationinclude aliphatic hydrocarbons, for example, pentane, hexane, etc.;alicyclic hydrocarbons, for example, cyclohexane, etc.; aromatichydrocarbons, for example, benzene, xylene, etc.; halogenatedhydrocarbons, for example, methylene chloride, chloroform,chlorobenzene, dichlorobenzene, etc.; nitrated hydrocarbons, forexample, nitromethane, etc.; nitrites, for example, acetonitrile,benzonitrile, etc.; ethers, for example, diethyl ether, diisopropylether, tetrahydrofuran, 1,4-dioxane, etc.; ketones, for example,acetone, methyl ethyl ketone, etc.; carboxylic acids, for example,acetic acid, etc.; acetic acid esters, for example, ethyl acetate, butylacetate, etc.; carbonates, for example, dimethyl carbonate, diethylcarbonate, ethylene carbonate, etc.; and alcohols, for example,methanol, ethanol, propanol, isopropanol, butanol, etc. These solventsmay be used singly or may be used in admixture of two or more kindsthereof.

The photoresist composition of the present invention is composed of theforegoing polymer compound (4) of the present invention and a solventand a photo acid generator and optionally, a basic substance andadditives as described later.

Examples of the solvent to be used for the photoresist composition ofthe present invention include glycol ethers, for example, propyleneglycol monoethyl ether, propylene glycol monomethyl ether, propyleneglycol monomethyl ether acetate, ethylene glycol monomethyl ether,ethylene glycol monomethyl ether acetate, ethylene glycol monomethylether propionate, ethylene glycol monobutyl ether, ethylene glycolmonobutyl ether acetate, diethylene glycol dimethyl ether, etc.; esters,for example, ethyl lactate, methyl 3-methoxypropionate, methyl acetate,ethyl acetate, propyl acetate, etc.; ketones, for example, acetone,methyl ethyl ketone, methyl isopropyl ketone, methyl isobutyl ketone,methyl amyl ketone, cyclopentanone, cyclohexanone, etc.; and ethers, forexample, diethyl ether, diisopropyl ether, dibutyl ether,tetrahydrofuran, 1,4-dioxane, etc. The solvent may be used singly or maybe used in admixture of two or more kinds thereof. The use amount of thesolvent is usually in the range of from 1 time by mass to 50 times bymass, and preferably in the range of from 2 times by mass to 25 times bymass relative to the polymer compound (4).

As the photo acid generator to be used for the photoresist compositionof the present invention, a customary known compound capable ofefficiently forming an acid upon exposure can be used. Examples of thephoto acid generator include sulfonium salts, for example,triphenylsulfonium hexafluoroantimonate, triphenylsulfoniumhexafluorophosphate, triphenylsulfonium trifluoromethylmethanesulfonate, triphenylsulfonium nonafluorobutanesulfonate, etc.;iodonium salts, for example, diphenyliodohexafluorosulfate, etc.;disulfones, for example, diphenyldisulfone, ditolylsulfone, etc.;triazine derivatives, for example,1-methyl-3,5-bistrichloromethyltriazine,1,3,5-tristrichloromethyltriazine, etc.; diazomethane derivatives, forexample, bis(cyclohexylsulfonyl)diazomethane,bis(phenylsulfonyl)diazomethane, etc.; sulfonic acid esters, forexample, (2′-nitrophenyl)methyl-p-toluenesulfonate,(2′,6′-dinitrophenyl)methyl-p-toluenesulfonate,1-phenyl-1-(4-methylphenyl)sulfonyloxy-1-benzoylmethane, etc.;diazonaphthoquinone; and benzoin tosylate. These photo acid generatorscan be used singly or can be used in admixture of two or more kindsthereof. The use amount of the photo acid generator can be chosendepending upon the strength of an acid which is formed upon irradiationwith radiations or the amount of the constitutional unit to be derivedfrom the tertiary alcohol derivative (1) in the polymer compound (4) andis in the range of from 0.1% by mass to 30% by mass, and preferably from0.5% by mass to 10% by mass relative to the polymer compound (4).

The photoresist composition of the present invention may further containa basic substance as the need arises. Examples of the basic substanceinclude amides, for example, formamide, N-methylformamide,N,N-dimethylformamide, acetamide, N-methylacetamide,N,N-dimethylacetamide, N-(1-adamantyl)acetamide, benzamide,N-acetylethanolamine, 1-acetyl-3-methylpiperidine, pyrrolidone,N-methylpyrrolidone, ε-caprolactam, δ-valerolactam, 2-pyrrolidinone,acrylamide, methacrylamide, t-butyl acrylamide, methylenebisacrylamide,methylenebismethacrylamide, N-methylolacrylamide, N-methoxyacrylamide,diacetone acrylamide, etc.; and amines, for example, pyridine,2-methylpyridine, 4-methylpyridine, nicotine, quinoline, acridine,imidazole, 4-methylimidazole, benzimidazole, pyrazine, pyrazole,pyrrolidine, piperidine, tetrazole, morpholine, 4-methylmorpholine,piperazine, diazabicyclo[2,2,2]octane, tributylamine, tripentylamine,trihexylamine, triheptylamine, trioctylamine, triethanolamine, etc.These basic substances may be used singly or may be used in admixture oftwo or more kinds thereof. In case of using a basic substance, thoughthe use amount thereof varies depending upon the kind of the basicsubstance, the basic substance is usually used in an amount in the rangeof from 0.01 times by mole to 10 times by mole, and preferably in therange of from 0.05 times by mole to 1 time by mole relative to the photoacid generator.

Furthermore, the photoresist composition of the present invention canalso be blended with various additives, for example, a surfactant, asensitizer, an anti-halation agent, a storage stabilizer, ananti-foaming agent, etc. as the need arises.

A pattern can be formed by coating the photoresist composition of thepresent invention on a substrate, prebaking at a temperature of fromabout 70° C. to 160° C., irradiating with radiations, especially an ArFexcimer laser, then post-exposure baking at a temperature of from 70° C.to 160° C. for 30 seconds or more and subsequently developing with wateror an alkaline developing solution.

For the exposure of the photoresist composition of the presentinvention, radiations having a wavelength of every kind, for example,ultraviolet rays, X-rays, etc. can be utilized. In the use forsemiconductor resist, excimer lasers, for example, g-rays, i-rays, XeCl,KrF, KrCl, ArF, ArCl, F₂, etc. are usually used. The exposure energy ispreferably in the range of from 0.1 to 1,000 mJ/cm², and more preferablyin the range of from 1 to 500 mJ/cm².

EXAMPLES

The present invention is specifically described below with reference tothe following Examples, but it should not be construed that the presentinvention is limited to these Examples. A weight average molecularweight (Mw) and dispersity (Mw/Mn) of a polymer compound were measuredby a GPC analysis [column: one prepared by connecting two columns ofTSK-gel SUPER HZM-H (a trade name, manufactured by Tosoh Corporation;diameter: 4.6 mm, length: 150 mm) and one column TSK-gel SUPER HZ2000 (atrade name, manufactured by Tosoh Corporation; diameter: 4.6 mm, length:150 mm) in series; detector: differential refractometer (RI); columntemperature: 40° C.; RI temperature: 40° C.; eluting solution:tetrahydrofuran; flow rate of the eluting solution: 0.35 mL/min;calibration curve: standard polystyrene].

Synthesis Example 1 Synthesis of methyl 4-cyclohexylidenebutanoate

A distillation column-provided four-necked flask having a volume of oneliter, which was equipped with a dropping funnel, a thermometer, astirring device and a reflux ratio regulator, was charged with 250 g(1.922 moles) of 1-vinyl-1-cyclohexanol, 415.6 g (3.843 moles) oftrimethyl orthoacetate and 1.4 g (0.019 moles) of propionic acid, andthe internal temperature was raised to 115° C. Heating was continued for12 hours while removing a fraction of not higher than 65° C. from acolumn top of the distillation column. After confirming thedisappearance of 1-vinyl-1-cyclohexanol by a gas chromatographicanalysis of the reaction solution, the reaction solution was distilledin vacuo. Fractions of from 120 to 130° C./1.2 kPa were collected toobtain 301.2 g (1.653 moles) of methyl 4-cyclohexylidenebutanoate. Theyield was 86.0%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

5.03 (1H, br), 3.66 (3H, s), 2.32 (4H, m), 2.13 (2H, br), 2.05 (2H, br),1.52 (6H, m)

Example 1 Synthesis of 4-(1′-hydroxycyclohexan-1′-yl)butanolide

A four-necked flask having a volume of one liter, which was equippedwith a dropping funnel, a thermometer and a reflux condenser, wascharged with 256.4 g (1.407 moles) of methyl 4-cyclohexylidenebutanoateas obtained in the method of Synthesis Example 1, 260 g of water and97.1 g (2.110 moles) of formic acid, and the internal temperature wasraised to 50° C. To this mixed solution, 239.2 g (2.111 moles) of 30% bymass hydrogen peroxide water was added dropwise over 3 hours. Aftercompletion of the dropwise addition, the mixture was stirred at 50° C.for 6 hours and then cooled to 25° C. 106.3 g (0.844 moles) of sodiumsulfite was added to the reaction mixture while maintaining the internaltemperature at not higher than 35° C. This reaction mixed solution wasseparated into an organic layer and an aqueous layer. 389.2 g of theorganic layer was distilled in vacuo. Fractions of 160° C./67 Pa werecollected to obtain 228.1 g (1.238 moles) of4-(1′-hydroxycyclohexan-1′-yl)butanolide. The yield was 88.0%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

4.34 (1H, t, J=7.5 Hz), 2.63 to 2.50 (2H, m), 2.35 to 2.2 (2H, m), 2.2to 2.05 (1H, m), 1.75 (1H, d, J=12.8 Hz), 1.71 to 1.42 (7H, m), 1.28(2H, m)

Boiling point: 160° C./67 Pa

Example 2 Synthesis of 4-(1′-methacryloyloxycyclohexan-1′-yl)butanolide

A four-necked flask having an inner volume of 300 mL, which was equippedwith a dropping funnel, a thermometer and a nitrogen introducing pipe,was charged with 30 g (162.8 mmoles) of4-(1′-hydroxycyclohexan-1′-yl)butanolide as obtained in the method ofExample 1, 100 mL of methylene chloride, 1.0 g (8.1 mmoles) ofdimethylaminopyridine and 28.9 g (276.8 mmoles) of methacryloylchloride. To this mixed solution, 29.7 g (293.0 mmoles) of triethylaminewas added dropwise at room temperature over 30 minutes. After completionof the dropwise addition, the mixture was stirred at room temperaturefor 20 hours. To the reaction mixture, 6.3 g (136.8 mmoles) of ethanolwas added dropwise, 100 mL of water was subsequently added dropwise, andthe mixture was stirred for 15 minutes. This reaction mixed solution wasseparated into an organic layer and an aqueous layer. The organic layerwas washed with 50 mL of water and then concentrated in vacuo. To 37 gof the concentrate, 70 mL of methyl isopropyl ketone was added, and themixture was cooled to −76° C. while stirring. The resulting mixture wasstirred at −76° C. for 3 hours, and a deposited crystal of4-(1′-methacryloyloxycyclohexan-1′-yl)butanolide was then filtered. Theobtained crystal was 16.4 g (65.1 mmoles), and the yield was 40.0%. Agas chromatographic analysis revealed that the filtrate contained 14.4 g(57.2 mmoles) of 4-(1′-methacryloyloxycyclohexan-1′-yl)butanolide. Atotal yield was 75.1%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

6.10 (1H, s), 5.58 (1H, s), 5.34 (1H, t, J=7.8 Hz), 2.57 to 2.50 (2H,m), 2.44 (1H, d, J=11.1 Hz), 2.19 to 2.08 (3H, m), 1.94 (3H, s), 1.71 to1.44 (7H, m), 1.28 (1H, m)

Melting point; 57.1 to 58.4° C.

Synthesis Example 2 Synthesis of methyl 4-adamantylidenebutanoate

A distillation column-provided four-necked flask having a volume of 100mL, which was equipped with a dropping funnel, a thermometer, a stirringdevice and a reflux ratio regulator, was charged with 25.0 g (140.2mmoles) of 2-vinyl-2-adamantanol, 30.3 g (280.5 mmoles) of trimethylorthoacetate and 0.2 g (2.8 mmoles) of propionic acid, and the internaltemperature was raised to 115° C. Heating was continued for 16 hourswhile removing a fraction of not higher than 65° C. from a column top ofthe distillation column. At that time, 0.2 g (2.8 mmoles) of propionicacid was added 16 times every one hour. The reaction mixture wasconcentrated at 110° C. under atmospheric pressure to obtain 26.9 g(115.0 mmoles) of methyl 4-adamantylidenebutanoate. The yield was 82.0%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

5.00 (1H, m), 3.67 (3H, s), 2.81 (1H, s), 2.31 (5H, br), 1.93 to 1.65(12H, m)

Example 3 Synthesis of 4-(2′-hydroxyadamantan-2′-yl)butanolide

A four-necked flask having a volume of 100 mL, which was equipped with adropping funnel, a thermometer and a reflux condenser, was charged with25.0 g (106.7 mmoles) of methyl 4-adamantylidenebutanoate as obtained inthe method of Synthesis Example 2, 63 g of water and 7.4 g (160.1mmoles) of formic acid, and the internal temperature was raised to 50°C. To this mixed solution, 18.2 g (160.1 mmoles) of 30% by mass hydrogenperoxide water was added dropwise over 3 hours. After completion of thedropwise addition, the mixture was stirred at 50° C. for 6 hours andthen cooled to 25° C. 8.1 g (64.1 mmoles) of sodium sulfite was added tothe reaction mixture while maintaining the internal temperature at nothigher than 35° C. This reaction mixed solution was filtered, and theobtained crystal was washed with 20 g of water and then dried in vacuoto obtain 17.0 g (71.8 mmoles) of4-(2′-hydroxyadamantan-2′-yl)butanolide. The yield was 67.3%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

5.10 (1H, t, J=8.1 Hz), 2.62 to 2.58 (2H, m), 2.36 to 2.01 (6H, m), 1.96to 1.72 (9H, m), 1.58 (2H, t, J=12.6 Hz)

Melting point: 135.7 to 137.4° C.

Example 4 Synthesis of 4-(2′-methacryloyloxyadamantan-2′-yl)butanolide

A four-necked flask having a volume of 300 mL, which was equipped with adropping funnel, a thermometer and a nitrogen introducing pipe, wascharged with 10.0 g (42.3 mmoles) of4-(2′-hydroxyadamantan-2′-yl)butanolide as obtained in the method ofExample 3, 50 mL of methylene chloride, 0.26 g (2.1 mmoles) ofdimethylaminopyridine and 6.6 g (63.5 mmoles) of methacryloyl chloride.To this mixed solution, 7.8 g (69.9 mmoles) of diazabicyclo[2,2,2]octanewas added dropwise at room temperature over 30 minutes. After completionof the dropwise addition, the mixture was stirred at room temperaturefor 20 hours. To the reaction mixed solution, 2.0 g (42.4 mmoles) ofethanol was added dropwise, 20 mL of water was subsequently addeddropwise, and the mixture was stirred for 15 minutes. This reactionmixed solution was separated into an organic layer and an aqueous layer.The organic layer was washed with 20 mL of water and then concentratedin vacuo. The concentrate was purified by silica gel columnchromatography to obtain 6.7 g (21.9 mmoles) of4-(2′-methacryloyloxyadamantan-2′-yl)butanolide. The yield was 51.8%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

6.10 (1H, s), 5.57 (1H, s), 5.26 (1H, dd, J=5.4 Hz, 8.4 Hz), 2.76 (1H,s), 2.62 (1H, s), 2.53 to 2.38 (3H, m), 2.26 to 2.23 (1H, m), 2.07 to2.02 (1H, m), 1.97 to 1.93 (3H, m), 1.93 (3H, s), 1.86 to 1.81 (4H, m),1.77 (2H, brs), 1.71 to 1.64 (2H, m)

Synthesis Example 3 Synthesis of4-(1′-chloroacetoxycyclohexan-1′-yl)butanolide

A four-necked flask having a volume of 300 mL, which was equipped with adropping funnel, a thermometer and a nitrogen introducing pipe, wascharged with 30 g (162.8 mmoles) of4-(1′-hydroxycyclohexan-1′-yl)butanolide as obtained in the method ofExample 1, 100 mL of methylene chloride, 1.0 g (8.1 mmoles) ofdimethylaminopyridine and 31.3 g (276.8 mmoles) of 2-chloroacetylchloride. To this mixed solution, 29.7 g (293.0 mmoles) of triethylaminewas added dropwise over 30 minutes. After completion of the dropwiseaddition, the mixture was stirred at room temperature for 20 hours. Tothe reaction mixed solution, 6.3 g (136.8 mmoles) of ethanol was addeddropwise, 100 mL of water was subsequently added dropwise, and themixture was stirred for 15 minutes. This reaction mixed solution wasseparated into an organic layer and an aqueous layer; and the organiclayer was washed with 50 mL of water and then concentrated in vacuo toobtain 35.2 g (135.1 mmoles) of4-(1′-chloroacetoxycyclohexan-1′-yl)butanolide. The yield was 83.0%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

4.87 (1H, t, J=7.7 Hz), 4.35 (2H, s), 2.36 to 2.30 (2H, m), 2.06 (2H, d,J=11.2 Hz), 1.67 to 1.65 (4H, m), 1.50 to 1.42 (6H, m)

Example 5 Synthesis of4-(1′-methacryloyloxyacetoxycyclohexan-1′-yl)butanolide

A four-necked flask having a volume of 500 mL, which was equipped with adropping funnel, a thermometer and a nitrogen introducing pipe, wascharged with 35.2 g (135.1 mmoles) of4-(1′-chloroacetoxycyclohexan-1′-yl)butanolide as obtained in the methodof Synthesis Example 3, 13.1 g (94.6 mmoles) of potassium carbonate, 0.5g (1.4 mmoles) of tetrabutylammonium iodide and 150 mL of toluene. Tothis mixed solution, 15.1 g (175.6 mmoles) of methacrylic acid was addeddropwise at room temperature over 30 minutes. After completion of thedropwise addition, the mixture was heated to 50° C. and stirred for 10hours. After cooling the reaction solution to room temperature, 150 mLof water and 100 mL of ethyl acetate were added. This mixed solution wasseparated into an organic layer and an aqueous layer; and the organiclayer was concentrated in vacuo and then purified by silica gel columnchromatography to obtain 30.6 g (98.6 mmoles) of4-(1′-methacryloyloxyacetoxycyclohexan-1′-yl)butanolide. The yield was72.9%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

6.15 (1H, s), 5.59 (1H, s), 5.13 (2H, s), 4.88 (1H, t, J=7.5 Hz), 2.36to 2.30 (2H, m), 2.06 (2H, d, J=11.5 Hz), 1.94 (3H, s), 1.67 to 1.65(4H, m), 1.50 to 1.42 (6H, m)

Synthesis Example 4 Synthesis of3-(1′-methacryloyloxycyclohexan-1′-yl)butanolide

A four-necked flask having a volume of 100 mL, which was equipped with adropping funnel and a thermometer, was charged with 10.0 g (118.9mmoles) of 2(5H)-furanone, 11.9 g (118.9 mmoles) of cyclohexanol and 5.2g (35.7 moles) of di-t-butyl peroxide, and the mixture was heated to130° C. After stirring for 20 hours, the reaction mixture was cooled to25° C. After adding 18.0 g (178.4 mmoles) of triethylamine and 30 mL ofmethylene chloride to the reaction mixture, 14.9 g (142.7 mmoles) ofmethacryloyl chloride was added dropwise at 25° C. After completion ofthe dropwise addition, the mixture was stirred at 25° C. for 13 hours,and 30 mL of water was then added dropwise. The reaction mixture wasseparated into an organic layer and an aqueous layer, and the aqueouslayer was extracted twice with 30 mL of methylene chloride. The organiclayer and the extract were mixed and concentrated in vacuo. Theconcentrate was purified by silica gel column chromatography to obtain1.7 g (6.9 mmoles) of 3-(1′-methacryloyloxycyclohexan-1′-yl)butanolide.The yield was 5.8%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

6.16 (1H, s), 5.56 (1H, s), 4.28 (2H, t, J=7.6 Hz), 2-65 (1H, m), 2.30(2H, t, J=7.6 Hz), 1.92 (3H, s), 1.65 to 1.60 (4H, m), 1.51 to 1.43 (6H,m)

Synthesis Example 5 Synthesis of2-(1′-methacryloyloxycyclohexan-1′-yl)butanolide

A four-necked flask having a volume of 500 mL, which was equipped with adropping funnel, a thermometer and a nitrogen introducing pipe, wascharged with 100 mL of tetrahydrofuran and 9.3 g (232.3 mmoles) of 60%by mass sodium hydride. This mixed solution was cooled to −10° C., and asolution of 20.0 g (232.3 mmoles) of γ-butyrolactone in tetrahydrofuran(20 mL) was added dropwise over one hour. After completion of thedropwise addition, the internal temperature was raised to 0° C., and themixture was stirred for 3 hours. Next, a solution of 22.8 g (232.3moles) of cyclohexanone in tetrahydrofuran (20 mL) was added dropwise atan internal temperature of 0° C. over one hour. After completion of thedropwise addition, the mixture was stirred at the same temperature for 5hours. Subsequently, 26.7 g (255.5 mmoles) of methacryloyl chloride wasadded dropwise at 0° C. over one hour. After completion of the dropwiseaddition, the temperature was raised to 30° C., and the mixture wasstirred for 7 hours. After adding 50 mL of water and 200 mL of ethylacetate to the reaction mixture, the mixture was separated into anorganic layer and an aqueous layer. The organic layer was concentratedin vacuo, and the concentrate was purified by silica gel columnchromatography to obtain 8.8 g (34.8 mmoles) of2-(1′-methacryloyloxycyclohexan-1′-yl)butanolide.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

6.13 (1H, s), 5.58 (1H, s), 4.33 (2H, br), 2.90 (1H, t, J=7.8 Hz), 2.10to 2.02 (2H, m), 1.93 (3H, s), 1.67 to 1.65 (4H, m), 1.50 to 1.42 (6H,m)

Synthesis Example 6 Synthesis of methyl 5-methyl-4-hexenate

A distillation column-provided four-necked flask having a volume of oneliter, which was equipped with a dropping funnel, a thermometer, astirring device and a reflux ratio regulator, was charged with 50.0 g(580.5 mmoles) of 2-vinyl-2-propanol, 139.5 g (1,161.0 mmoles) oftrimethyl orthoacetate and 1.3 g (17.4 mmoles) of propionic acid, andthe internal temperature was raised to 115° C. Heating was continued for12 hours while removing a fraction of not higher than 65° C. from acolumn top of the distillation column. After confirming thedisappearance of 2-vinyl-2-propanol by a gas chromatographic analysis ofthe reaction solution, the reaction solution was distilled in vacuo.Fractions of from 60 to 65° C./1.2 kPa were collected to obtain 62.2 g(437.1 mmoles) of methyl 5-methyl-4-hexenate. The yield was 75.3%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

5.09 (1H, m), 3.67 (3H, s), 2.30 (4H, br), 1.68 (3H, s), 1.62 (3H, s)

Synthesis Example 7 Synthesis of 4-(2′-hydroxypropan-2′-yl)butanolide

A four-necked flask having a volume of 500 mL, which was equipped with adropping funnel, a thermometer and a reflux condenser, was charged with40 g (281.3 mmoles) of methyl 5-methyl-4-hexenate as obtained in themethod of Synthesis Example 6, 80 g of water and 20.7 g (450.1 mmoles)of formic acid, and the internal temperature was raised to 50° C. Tothis mixed solution, 51.0 g (450.1 mmoles) of 30% by mass hydrogenperoxide water was added dropwise over 3 hours. Furthermore, the mixturewas stirred at 50° C. for 6 hours and then cooled to 25° C. 25.5 g(202.6 mmoles) of sodium sulfite was added to the reaction mixture whilemaintaining the internal temperature at not higher than 35° C. Thisreaction mixed solution was separated into an organic layer and anaqueous layer; the organic layer was concentrated in vacuo; and theobtained concentrated solution was distilled in vacuo. Fractions of 130to 140° C./400 Pa were collected to obtain 21.3 g (148.0 mmoles) of4-(2′-hydroxypropan-2′-yl)butanolide. The yield was 52.6%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

4.32 (1H, t, J=7.5 Hz), 2.60 to 2.53 (2H, m), 2.21 to 2.17 (2H, m), 1.33(3H, s), 1.19 (3H, s)

Synthesis Example 8 Synthesis of4-(2′-methacryloyloxypropan-2′-yl)butanolide

A four-necked flask having a volume of 300 mL, which was equipped with adropping funnel, a thermometer and a nitrogen introducing pipe, wascharged with 10.0 g (69.4 mmoles) of4-(2′-hydroxypropan-2′-yl)butanolide as obtained in the method ofSynthesis Example 7, 50 mL of methylene chloride and 9.4 g (90.2 mmoles)of methacryloyl chloride. To this mixed solution, 11.2 g (111.0 mmoles)of triethylamine was added dropwise over 30 minutes. After completion ofthe dropwise addition, the mixture was stirred at room temperature for 6hours. To the reaction mixed solution, 50 mL of water was addeddropwise, and the mixture was stirred for 15 minutes and then separatedinto an organic layer and an aqueous layer. The obtained organic layerwas washed with 50 mL of water and then concentrated in vacuo. Theconcentrate was purified by silica gel column chromatography to obtain9.4 g (44.3 mmoles) of 4-(2′-methacryloyloxypropan-2′-yl)butanolide. Theyield was 63.8%.

¹H-NMR (300 MHz, CDCl₃, ppm, TMS) δ:

5.98 (1H, s), 5.53 (1H, s), 4.61 (1H, t, J=7.3 Hz), (2H, t, J=10.0 Hz),2.30 to 2.21 (2H, m), 1.90 (3H, s), (3H, s), 1.57 (3H, s)

Example 6 Synthesis of Polymer Compound (Polymer Compound 1) Having theFollowing Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with the whole of 5.9 g (25.0 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 6.3 g (25.0 mmoles) of4-(1′-methacryloyloxycyclohexan-1′-yl)butanolide as obtained in themethod of Example 2, 44 mL of methyl ethyl ketone and 0.66 g (4.0mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was heated at 80° C. and polymerized for 4 hours. The obtainedreaction solution was added dropwise in 1,000 mL of methanol at roomtemperature while stirring to obtain a white precipitate. The obtainedprecipitate was separated by filtration and dried in vacuo for 10 hoursto obtain 5.5 g of desired Polymer Compound 1. Mw was 7,400, and Mw/Mnwas 1.55.

Example 7 Synthesis of Polymer Compound (Polymer Compound 2) Having theFollowing Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with the whole of 5.9 g (25.0 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 7.6 g (25.0 mmoles) of4-(2′-methacryloyloxyadamantan-2′-yl)butanolide as obtained in themethod of Example 4, 44 mL of methyl ethyl ketone and 0.66 g (4.0mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was heated at 80° C. and polymerized for 4 hours. The obtainedreaction solution was added dropwise in 1,000 mL of methanol at roomtemperature while stirring to obtain a white precipitate. The obtainedprecipitate was separated by filtration and dried in vacuo for 10 hoursto obtain 6.5 g of desired Polymer Compound 2. Mw was 7,500, and Mw/Mnwas 1.61.

Example 8 Synthesis of Polymer Compound (Polymer Compound 3) Having theFollowing Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with the whole of 5.9 g (25.0 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 7.8 g (25.0 mmoles) of4-(1′-methacryloyloxyacetoxycyclohexan-1′-yl)butanolide as obtained inthe method of Example 5, 44 mL of methyl ethyl ketone and 0.66 g (4.0mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was heated at 80° C. and polymerized for 4 hours. The obtainedreaction solution was added dropwise in 1,000 mL of methanol at roomtemperature while stirring to obtain a white precipitate. The obtainedprecipitate was separated by filtration and dried in vacuo for 10 hoursto obtain 3.6 g of desired Polymer Compound 3. Mw was 7,800, and Mw/Mnwas 1.58.

Synthesis Example 9 Synthesis of Polymer Compound (Polymer Compound 4)Having the Following Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with 5.9 g (25.0 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 6.3 g (25.0 mmoles) of3-(1′-methacryloyloxycyclohexan-1′-yl)butanolide as obtained in themethod of Synthesis Example 4, 44 mL of methyl ethyl ketone and 0.66 g(4.0 mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was polymerized at 80° C. for 4 hours. The obtained reactionsolution was added dropwise in 1,000 mL of methanol at room temperaturewhile stirring to obtain a white precipitate. The obtained precipitatewas separated by filtration and dried in vacuo for 10 hours to obtain5.3 g of desired Polymer Compound 4. Mw was 7,300, and Mw/Mn was 1.72.

Synthesis Example 10 Synthesis of Polymer Compound (Polymer Compound 5)Having the Following Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with 5.9 g (25.0 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 6.3 g (25.0 mmoles) of2-(1′-methacryloyloxycyclohexan-1′-yl)butanolide as obtained in themethod of Synthesis Example 5, 44 mL of methyl ethyl ketone and 0.66 g(4.0 mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was polymerized at 80° C. for 4 hours. The obtained reactionsolution was added dropwise in 1,000 mL of methanol at room temperaturewhile stirring to obtain a white precipitate. The obtained precipitatewas separated by filtration and dried in vacuo for 10 hours to obtain5.8 g of desired Polymer Compound 5. Mw was 7,500, and Mw/Mn was 1.63.

Synthesis Example 11 Synthesis of Polymer Compound (Polymer Compound 6)Having the Following Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with 5.9 g (25.0 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 5.3 g (25.0 mmoles) of4-(2′-methacryloyloxypropan-2′-yl)butanolide as obtained in the methodof Synthesis Example 8, 44 mL of methyl ethyl ketone and 0.66 g (4.0mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was polymerized at 80° C. for 4 hours. The obtained reactionsolution was added dropwise in 100 mL of methanol at room temperaturewhile stirring to obtain a white precipitate. The obtained precipitatewas separated by filtration and dried in vacuo for 10 hours to obtain5.8 g of desired Polymer Compound 6. Mw was 7,400, and Mw/Mn was 1.75.

Example 9 Synthesis of Polymer Compound (Polymer Compound 7) Having theFollowing Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with 4.39 g (18.7 mmoles) of2-methacryloyloxy-2-methyladamantane, 2.96 g (12.5 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 4.72 g (18.7 mmoles) of4-(1′-methacryloyloxycyclohexan-1′-yl)butanolide as obtained in themethod of Example 2, 44 mL of methyl ethyl ketone and 0.66 g (4.0mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was polymerized at 80° C. for 4 hours. The obtained reactionsolution was added dropwise in 100 mL of methanol at room temperaturewhile stirring to obtain a white precipitate. The obtained precipitatewas separated by filtration and dried in vacuo for 10 hours to obtain5.25 g of desired Polymer Compound 7. Mw was 7,300, and Mw/Mn was 1.60.

Example 10 Synthesis of Polymer Compound (Polymer Compound 8) Having theFollowing Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with the whole of 4.39 g (18.7 mmoles) of2-methacryloyloxy-2-methyladamantane, 2.96 g (12.5 moles) of1-hydroxy-3-methacryloyloxyadamantane, 4.72 g (18.7 mmoles) of4-(1′-methacryloyloxycyclohexan-1′-yl)butanolide as obtained in themethod of Example 2, 44 mL of methyl ethyl ketone and 0.33 g (2.0mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was polymerized at 80° C. for 6 hours. The obtained reactionsolution was added dropwise in 1,000 mL of methanol at room temperaturewhile stirring to obtain a white precipitate. The obtained precipitatewas separated by filtration and dried in vacuo for 10 hours to obtain5.45 g of desired Polymer Compound 8. Mw was 13,000, and Mw/Mn was 1.60.

Example 11 Synthesis of Polymer Compound (Polymer Compound 9) Having theFollowing Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with 4.39 g (18.7 mmoles) of2-methacryloyloxy-2-methyladamantane, 2.96 g (12.5 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 5.69 g (18.7 mmoles) of4-(2′-methacryloyloxyadamantan-2′-yl)butanolide as obtained in themethod of Example 4, 44 mL of methyl ethyl ketone and 0.66 g (4.0mmoles) of azoisobutyronitrile under a nitrogen atmosphere, and themixture was polymerized at 80° C. for 4 hours. The obtained reactionsolution was added dropwise in 1,000 mL of methanol at room temperaturewhile stirring to obtain a white precipitate. The obtained precipitatewas separated by filtration and dried in vacuo for 10 hours to obtain5.30 g of desired Polymer Compound 9. Mw was 7,300, and Mw/Mn was 1.60.

Synthesis Example 12 Synthesis of Polymer Compound (Polymer Compound 10)Having the Following Structure

A round bottom flask having a volume of 100 mL, which was equipped witha nitrogen inlet, a stirrer, a reflux condenser and a thermometer, wascharged with 4.39 g (18.7 mmoles) of2-methacryloyloxy-2-methyladamantane, 2.96 g (12.5 mmoles) of1-hydroxy-3-methacryloyloxyadamantane, 3.18 g (18.7 mmoles) ofα-methacryloyloxy-γ-butyrolactone, 44 mL of methyl ethyl ketone and 0.66g (4.0 mmoles) of azoisobutyronitrile under a nitrogen atmosphere, andthe mixture was polymerized at 80° C. for 4 hours. The obtained reactionsolution was added dropwise in 1,000 mL of methanol at room temperaturewhile stirring to obtain a white precipitate. The obtained precipitatewas separated by filtration and dried in vacuo for 10 hours to obtain6.06 g of desired Polymer Compound 10. Mw was 10,000, and Mw/Mn was1.50.

Examples 12 to 17 and Comparative Examples 1 to 4 Evaluation ofDissolution Rate and Maximum Amount of Swelling

100 parts by mass of each of Polymer Compounds 1 to 10 obtained inExamples 6 to 11 and Synthesis Examples 9 to 12 and 3 parts by mass of aphoto acid generator (TPS-109, manufactured by Midori Kagaku Co., Ltd.)were dissolved in a mixed solvent of propylene glycol monomethyl etheracetate/ethyl lactate (1/1) (mass ratio) to prepare ten kinds ofphotoresist compositions each having a concentration of the polymercompound of 12% by mass. These photoresist compositions were eachfiltered using a filter (made of a tetrafluoroethylene resin (PTFE))(0.2 μm) and then coated on a quartz substrate of 1 inch in size on thesurface of which had been vacuum vapor deposited a gold electrode by aspin coating method, thereby forming a photosensitive film having athickness of about 300 nm. These quartz substrates were each prebaked ona hot plate at a temperature of 130° C. for 90 seconds, subsequentlyexposed with an ArF excimer laser having a wavelength of 193 nm at anexposure amount of 100 mJ/cm² and then post-exposure baked at 130° C.for 90 seconds. These quartz substrates were each set in a quartzcrystal microbalance device “RQCM” (manufactured by Maxtek, Inc.) anddeveloped with a 2.38% by mass tetramethylammonium hydroxide aqueoussolution for 120 seconds. A change in frequency of the quartz substrateduring the development treatment was monitored with a lapse of time; andthereafter, the obtained change in frequency was reduced into a changein the film thickness, thereby defining a dissolution rate and a maximumamount of swelling.

<Evaluation of Pattern Shape>

100 parts by mass of each of Polymer Compounds 1 to 10 obtained inExamples 6 to 11 and Synthesis Examples 9 to 12, 3 parts by mass of aphoto acid generator (TPS-109, manufactured by Midori Kagaku Co., Ltd.)and 0.25 parts by mass of triethanolamine were dissolved in a mixedsolvent of propylene glycol monomethyl ether acetate/ethyl lactate (1/1)(mass ratio) to prepare ten kinds of photoresist compositions eachhaving a concentration of the polymer compound of 12% by mass. Thesephotoresist compositions were each filtered using a filter (made of atetrafluoroethylene resin (PTFE)) (0.2 μm). On a silicon wafer having adiameter of 10 cm on which an antireflection film (base film) having athickness of about 100 nm had been formed by coating a propylene glycolmonomethyl ether acetate solution of a cresol/novolak resin (PS-6937,manufactured by Gun Ei Chemical Industry Co., Ltd.) in a concentrationof 6% by mass by a spin coating method and baking on a hot plate at 200°C. for 90 seconds, each of the foregoing photoresist compositions wascoated by a spin coating method to form a photoresist film having athickness of about 300 nm. These were each prebaked on a hot plate at130° C. for 90 seconds and then exposed with an ArF excimer laser havinga wavelength of 193 nm by a double beam interference method.Subsequently, the exposed resist film was post-exposure baked at 130° C.for 90 seconds and then developed with a 2.38% by masstetramethylammonium hydroxide aqueous solution for 60 seconds, therebyforming a 1:1 line-and-space pattern having a line width of 100 nm. Theshape of the obtained resist pattern was observed by a scanning electronmicroscope (SEM), and a line width fluctuation (LWR) in a line width of100 nm was also observed. As to LWR, a line width was detected at pluralpositions within a measuring monitor using a critical-dimension scanningelectron microscope (SEM), and a 3σ value (σ: standard deviation) ofthat line width was defined as an index for LWR.

TABLE 1 Dissolution rate Maximum Used at amount of polymer developmentswelling LWR Pattern compound (nm/sec) (nm) (nm) shape Example 12Polymer 685 5 7.9 Good Compound 1 Example 13 Polymer 534 6 7.6 GoodCompound 2 Example 14 Polymer 457 6 7.8 Good Compound 3 Example 15Polymer 702 7 7.8 Good Compound 7 Example 16 Polymer 510 8 7.7 GoodCompound 8 Example 17 Polymer 312 6 7.8 Good Compound 9 ComparativePolymer 76 18 10.3 Poor Example 1 Compound 4 Comparative Polymer 85 2110.7 Poor Example 2 Compound 5 Comparative Polymer 103 58 11.8 PoorExample 3 Compound 6 Comparative Polymer 60 40 12.3 Poor Example 4Compound 10

It is understood from Table 1 that in the case of a photoresistcomposition using a polymer compound obtained by polymerizing onecontaining the polymerizable compound represented by the general formula(1) of the present invention (Examples 12 to 17), the dissolution ratein an alkaline developing solution to be used in the development processin manufacturing a photoresist pattern is very high, the maximum amountof swelling at the development is very small, and LWR is improved ascompared with the case of a photoresist composition obtained bypolymerizing one not containing the polymerizable compound representedby the general formula (1) of the present invention (ComparativeExamples 1 to 4).

INDUSTRIAL APPLICABILITY

The tertiary alcohol derivative (1) and the polymer compound (4) of thepresent invention are useful as a raw material of a photoresistcomposition. Also, the photoresist composition of the present inventionis useful as a photoresist composition for manufacturing an electronicdevice.

1. A tertiary alcohol derivative represented by formula (1):

wherein R¹ and R² individually represent a linear, branched or cyclicalkylene group having from 2 to 9 carbon atoms, which may contain anoxygen atom at an arbitrary position, and R¹ and R² may together form aring with a carbon atom to which R¹ and R² are bonded; R³ represents ahydrogen atom or a methyl group; W represents a linear, branched orcyclic alkylene group having from 1 to 10 carbon atoms; and n represents0 or
 1. 2. The tertiary alcohol derivative according to claim 1, whereinW is a methylene group or an ethane-1,1-diyl group.
 3. The tertiaryalcohol derivative according to claim 1, wherein n is
 0. 4. A method formanufacturing a tertiary alcohol derivative represented by formula (1):

wherein R¹ and R² individually represent a linear, branched or cyclicalkylene group having from 2 to 9 carbon atoms, which may contain anoxygen atom at an arbitrary position, and R¹ and R² may together form aring with a carbon atom to which R¹ and R² are bonded; R³ represents ahydrogen atom or a methyl group; W represents a linear, branched orcyclic alkylene group having from 1 to 10 carbon atoms; and n represents0 or 1; which comprises, as a first step, oxidizing a carboxylic acidderivative represented by formula (2) in the presence of water:

wherein R¹ and R² are as defined in formula (1); and R⁴ represents analkyl group having from 1 to 10 carbon atoms, an aryl group having from6 to 12 carbon atoms or an aralkyl group having from 7 to 13 carbonatoms; or oxidizing a carboxylic acid derivative represented by formula(2′):

wherein R¹ and R² are as defined in formula (1), thereby obtaining atertiary alcohol represented by formula (3):

wherein R¹ and R² are as defined in formula (1), and, as a second step,subsequently allowing the tertiary alcohol to react with a polymerizablegroup introducing agent, or allowing the tertiary alcohol to react witha connecting group introducing agent and then to react with apolymerizable group introducing group.
 5. A polymer compound obtained bypolymerizing at least the tertiary alcohol derivative according to claim1 as one of one or more raw materials.
 6. A photoresist compositioncomprising the polymer compound according to claim 5 and a photo acidgenerator.